Personal Video Recorder (PVR) systems, which are typically integrated with a cable or satellite television set-top box (STB), are used, amongst other functions, to record broadcasted programs onto a hard disk of the PVR. One example of a PVR system is described in PCT Published Patent Application WO2000/01149 of NDS Ltd. and corresponding US Published Patent Application 2003/088872 of Maissel, et al., the disclosures of which are hereby incorporated herein by reference.
Resource conflicts may occasionally arise when a PVR is used. For example, in a PVR with a single tuner, it is not possible to view live TV of one channel and record TV broadcast from another channel simultaneously or to record more than one program simultaneously. Similarly, in a PVR with two tuners, it is not possible to watch live TV and record more than one program simultaneously or to record more than two programs simultaneously. The hard disk and disk drive are typically also limited resources of a PVR. For example, the hard disk may fill up or there may be too many input/output requests for the disk drive to perform, such as when recording and/or playing multiple programs. Another example of a limited resource is booking conflicts, where too many events are booked for recording at the same time, thus potentially creating a predicted future resource conflict. Booking conflicts are special in that they require a check of future resources, as opposed to an immediate requirement for a resource.
When a PVR is connected to a single television (hereinafter “TV”), conflict resolutions are typically handled in the following manner. First, the PVR tries to resolve the conflict automatically. For example, if the disk is full then the PVR will delete or overwrite the oldest recorded program first. However, conflicts may arise that the PVR cannot handle automatically, for example, when all the programs stored on the disk are marked as “keep” or when the viewer has requested to record two programs simultaneously but also wants to watch live TV and the PVR only has two tuners. In such cases, typically the PVR sends an on-screen display to the TV for the viewer to decide what action to take. The choices may be for example, “forgo live TV”, “cancel recording 1” or “cancel recording 2”. If the resource conflict is not resolved by the viewer within a defined time, the PVR will perform default conflict resolution, for example, canceling some conflicting booked recordings until there are no more conflicts.
The following is a list of patent publications which are representative of the art related to conflict resolution for a single TV: US Published Patent Applications 2003/0198462 of Bumgardner, et al. and 2002/0168178 of Rodriguez, et al. and PCT Published Patent Application WO2004/049714 of United Video Properties Inc.
A single PVR, and therefore the resources thereon, are sharable by a plurality of TVs. Each TV is typically connected to the outputs (digital or analogue) of the PVR via a user interface unit. Similarly, multiple TVs may share multiple PVRs connected by a network. This set up is known as a multi-TV PVR. Therefore, the viewer of each TV can share the tuning and recording facilities of the PVR(s). In a multi-TV PVR environment resource conflicts may arise, for example, conflicts associated with the tuners, hard disk and disk drive. Additionally, in a networked environment, network bandwidth is also a limited resource and the network typically has a data transfer limit. For example, where a network is used to view TV then overuse of a network may make the network response sluggish so that TV viewing or response to “trick modes” is compromised which is generally unacceptable in the TV world.
Of general interest is US Published Patent Application 2003/0079227 of Knowles, et al., which describes a multi-user integrated program guide for use with a multi-TV PVR. Knowles describes resolving user conflicts relating to double purchasing of the same program or canceling someone else's booked recording. Knowles does not describe or suggest resolving conflicts related to resources of a multi-TV (networked) PVR system. Also of interest is U.S. Pat. No. 6,637,029 to Maissel, et al., which describes a system for determining tastes and preferences of viewers by inference from viewing habits.
The following references are also believed to represent the state of the art:
US Published Patent Application 2004/0156614 of Bumgardner, et al.;
US Published Patent Application 2004/0103434 of Ellis;
US Published Patent Application 2003/0066092 of Wagner, et al.;
PCT Published Patent Application WO 2002/093299 of Scientific-Atlanta, Inc.;
PCT Published Patent Application WO 2000/052930 of Starsight Telecast, Inc.;
European Published Patent Application EP 01469676 of United Video Properties Inc.;
European Published Patent Application EP 1213919 of United Video Properties Inc.;
U.S. Pat. No. 6,785,901 to Horiwitz, et al.; and
U.S. Pat. No. 6,505,348 to Knowles, et al.
The disclosures of all references mentioned above and throughout the present specification, as well as the disclosures of all references mentioned in those references, are hereby incorporated herein by reference.